1. Field of the Invention
This invention relates to a document searching system which enables to search discretionally the documents described by plural different languages (multilingual documents) according to the key word written by the designated language (e.g. native language) and to display the search result by the designated language.
2. Discussion of the Related Art
Recently information must be exchanged between areas having different languages from each other due to the development of communication networks, including the Internet. On the other hand, the information is currently delivered by the use of the electrical memory devices (such as databases, CD-ROMs, etc.). For example, information searching service systems use of databases of documents from science, technology and patents are prevalent.
When documents are searched for by the words used in the documents, it should be noticed that each author of their document may use different words to describe the same meaning, material, matter, etc. Therefore, the search result may miss some expected documents when the searcher fails to designate some alternative words. To prevent such errors, it is known to use a synonym dictionary to automatically collect the words or terms having identical or equivalent meanings and to make a search formula using the collected terms.
When the database to be searched is written in another language from the searcher""s native language, the searcher should translate the key words for searching from their native language to that used in the database prior to inputting the search. Such a searching system has been provided in which the search formula input is written by the searcher""s native language and then is translated automatically to that used in the database to be searched. The search is then carried out in the database. Such a system is disclosed by Japanese Kokai Patent No. 8-202721 where the search result is translated automatically to the searcher""s native language and then displayed.
The documents to be searched are generally text data only, but they are usually supplemented by objects such as drawings, photographs or animations. As for the search result, each object is usually arranged in a designated area and shown together with the text data on the same page. In this case, the object is linked to the text data by assigning a tag with specified function in the document, and such text is referred to as hyper-linked text. SGML and HTML, used in WWW, are two kinds of texts of this type. Such software such as viewers or browsers are generally utilized to interpret and develop the hyper-linked text and then display it.
Such a system may be constructed by combining these techniques mentioned above as follows. When the language used to input the search condition formula is different from that of the documents to be searched, the search condition formula is translated automatically to an equivalent one written in another language so as to include synonyms. The search is then carried out and then the search result is automatically translated to and displayed by the language defined during the input of the search condition formula.
There are several problems to be solved for the systems described above as follows.
First, the system automatically generates the synonyms of the search formula and translates them to other languages. This happens even if the documents to be searched are written in the same language used in the original search terms. Thus, if both the searcher""s native language and the other languages are included this may complicate the search.
Second, when the documents to be searched include more than three languages such as Japanese, English, French and German, plural translating functions and means, that is, from English to Japanese, from English to French, and from English to German, are required. The translating function is generally applied to sentences and therefore, it is of a high technical level, has a large structure and is a complicated program. This causes the system response to be lowered when the program is packaged.
Third, when the search result is automatically translated, the whole result is unconditionally translated to the language used in the input of the search condition and therefore a longer time is required to translate the search results automatically.
Fourth, when the hypertext document is displayed with a format similar to the original document, this format depends on the intention of the author of the document. Therefore sometimes it may be inconvenient for the searcher because this format lacks linking at an expected location. When the text portion, such as each segment (paragraph) in the text, and the related object are displayed separately, useful formatting of the display is required to enable analysis of the document. The relationship between each element on the display, for instance, the relation between the drawing and the portion of the document referring to it, should be able to be confirmed on the display.
To solve these problems, an interactive and useful document searching system for multilingual documents is required which allows display of the search results more effectively and within a short time.
The document searching system for multilingual documents of the present invention is characterized as described below to solve these problems.
The system of the present invention is provided with and characterized by an input means to input a search command including a search key word designated by the searcher; a translation control means for the key word to translate the key word input by the searcher into another language used in the document to be searched; a search formula generating means to generate a search formula from the key word transferred from the translation control means based on the key word; a search means to search a document storage means according to the search formula transferred from the search formula generating means; a search result storage means to store the searched and selected documents; another translation control means for the search result to translate the documents stored in the search result storage means to the designated language; and a display means to display the results of the translation.
The document searching system for multilingual documents of the present invention is provided with two translation means independent of each other. One is a translation control means for the key word to translate the key word written by the searcher""s native language and the other is a translation control means for the search result which may translate the entire text of the documents selected as a search result. As for the key word translation means, a simple translation system shall be applied because the objects of the translation are words such as nouns, verbs and so forth. On the other hand, for the search result translation means, a high-level translation system shall be applied because the objects of the translation are common sentences and the appropriate translation is required by deducing from the context of the document.
Due to the application of the simple translation system to the processing steps of the free key word translation means where the search formula may be changed, added, modified or deleted frequently to improve the exactness of the search result, the processing speed in these steps is not decreased so that the whole system response may speed up.